By 1974, when she became the first female biology professor to be awarded tenure at Harvard University, Ruth Hubbard was shifting her focus from the laboratory to the petri dish of politics. Already an antiwar activist, she became a prominent feminist critic of science and later raised privacy concerns in the debate over gene research.

What constitutes science, she told the Globe in 1990, usually is decided by “a self-perpetuating, self-reflexive group: by the chosen for the chosen,’’ and those “chosen’’ historically were upper-class white men.

“Women and nonwhite, working-class and poor men have largely been outside the process of science-making,’’ Dr. Hubbard told The New York Times in 1981. “Though we have been described by scientists, by and large we have not been the describers and definers of scientific reality. We have not formulated the questions scientists ask, nor have we answered them. This undoubtedly has affected the content of science, but it has also affected the social context and the ambience in which science is done.’’

An award-winning biochemist who studied vision earlier in her career, Dr. Hubbard died last Thursday in her Cambridge home. She was 92 and her health had declined significantly in the past couple of years.

At Harvard in the 1970s, she taught groundbreaking courses on biology and women’s issues that examined the consequences of women largely being excluded from science and medicine.

For many years before that, she herself was a top researcher. With her second husband, George Wald, she shared the Paul Karrer Medal in 1967 for their work on the photochemistry of vertebrates and invertebrates. That same year he shared the Nobel Prize for physiology or medicine for his research on primary physiological and chemical visual processes.

Then one day in 1969, she happened upon protesters criticizing the discrimination women in science faced. “I was absolutely flabbergasted,’’ Dr. Hubbard told the Globe years later. “I was a scientist. And they allowed me to work at Harvard. So how come there was discrimination?’’

She found part of the answer by looking at her own feelings. “I really thought men were smarter, more interesting, better company, and I played up to them,’’ she said, reflecting on how she had lived her life until the late 1960s. “I had one woman friend.’’

To challenge the norm, she wrote and edited books that dissected the patterns of who gets to ask the scientific questions that set and define society’s roles. Because scientists “have been predominantly university-trained white males from privileged social backgrounds, the bias has been narrow’’ and their research “often reveals more about the investigator than about the subject being researched,’’ she wrote in “Have Only Men Evolved?’’ — an essay published in the 1982 book “Biological Woman — The Convenient Myth,’’ which she co-edited.

“Since women have not figured in the paradigm of evolution,’’ she added, “we need to rethink our evolutionary history.’’

Born Ruth Hoffmann in 1924, she was the daughter of two physicians, Richard Hoffmann and the former Helene Ehrlich, and grew up in Vienna, where her parents were committed socialists and her mother was a talented pianist. When Nazi Germany annexed Austria in 1938, the family moved to Brookline, and Dr. Hubbard graduated from Brookline High School.

“She always felt like a foreigner in the United States,’’ said her son, Elijah Wald of Cambridge, a writer and musician. “She had been forced to leave Europe, but she never stopped feeling like a European who ended up here.’’

That outsider role has “given me the internal right and freedom to shape my life according to my needs — not to have to fit models of what it means to be a professional or wife or mother or hostess,’’ she told the Globe in 1990. “When I look at some of my friends, I think I’ve had an easier time shucking off things that I ­haven’t wanted to participate in. I call it arrogance, and it is in a certain sense. But it comes out of lack of identification with a model that I must fit.’’

While she was a premed student at Radcliffe College, she met and married Frank Hubbard. They traveled through Europe on a motorcycle while Frank, who became a leading maker and restorer of harpsichords, researched the instrument.

The couple settled in a Cambridge cold-water flat and she went to work at George Wald's Harvard lab. “She was the best graduate student I ever had,’’ he told the Globe in 1990. She received a doctorate in biology from Radcliffe, and she and Wald fell in love. Keeping their relationship secret for more than a decade, they published papers and eventually married in the late 1950s after each of their previous marriages ended in divorce.

She wrote extensively upon turning to social criticism of the sciences in the mid-1970s. Her books include “Women Look at Biology Looking at Women,’’ which she edited with Mary Sue Henifin and Barbara Fried; and “The Politics of Women’s Biology’’ and “Profitable Promises: Essays on Women, Science and Health,’’ both of which she wrote. Dr. Hubbard didn’t soften her critiques, even when it came to her employer. “I have felt, and I still feel, that Harvard is a bad place for women,’’ she said in a 1981 oral history interview, adding that “women are still socialized to sit at the feet of great men.’’

Dr. Hubbard’s younger brother, Alexander Hoffmann, who died in 2009, was a lawyer for liberal causes who counted among his clients Cesar Chavez and members of the Black Panther Party. With her husband, who died in 1997, Dr. Hubbard was an antinuclear activist and an antiwar activist, and she was once arrested for civil disobedience.

With her son, she wrote the book “Exploding the Gene Myth: How Genetic Information is Produced and Manipulated by Scientists, Physicians, Employers, Insurance Companies, Educators, and Law Enforcers,’’ which was published in the 1990s.

“There are many more productive things to do than to worry about the possible implications of genetic prophecies,’’ Dr. Hubbard, who was a member of the Council for Responsible Genetics, wrote in the Globe in 1999. “It’s certainly not worth the risks of discrimination that will result from the inevitable loss of privacy.’’

A service will be held at a later date for Dr. Hubbard, who in addition to her son leaves her daughter, Deborah Wald of San Francisco; a foster brother, Benjamin Goldstein of Lexington; and two grandsons.

During childhood in Austria, Dr. Hubbard was a piano prodigy, and in later years she often attended concerts in Cambridge. With her long silver hair, she was a familiar figure in many circles, and she began writing poetry after retiring — or taking an “extended sabbatical,’’ as she called it.

“She always liked complicated music and she liked complicated books,’’ Elijah said of his mother’s tastes, which included saxophonist John Coltrane's jazz and the novels of William Faulkner and Henry James.

On the cusp of retiring in 1990, she mused that the path she took might have befuddled the scientists with whom she once worked. “You know, I have no idea what my colleagues think of me,’’ she told the Globe. “I think at best they’re puzzled. At worst, they think I’ve gone off my rocker.’’

Bryan Marquard can be reached at bryan.marquard@globe.com.